I have this problem with pretty much everything I try to work on in keyshot. At the base of my object where it meets the ground, the shadow is really choppy. I'm using the real time render set to 600 seconds for this render. In the realtime settings I have it set to 5 on shadow quality and 16 on ray bounces.
Also, I'm not sure if it "should be" this way or not, but on the inside of the bottom of some of my parts I get a line between the part and the shadow.
Does this help at all..?
http://keyshot.com/forum/index.php?topic=1890.0
It appears that your object is slightly rotated, intersecting the ground plane on the left hand side. Increase your ground shadow quality in the realtime tab to get better quality ground shadows.
That's what I was thinking is that the model was rotated slightly but I couldn't see anywhere where it was. I'll keep an eye out for that and see if it happens again. On the note about the rough looking shadows, I always have my shadow quality in the real time set to 5. ;/
Sometime is may be necessary to go into the advanced settings (enable under preferences) and adjust the ground grid size to a smaller number.
I enabled the advanced settings but do not see any extra options? :o
It is in the environment tab, sorry.